Field Performance of a Rapid Diagnostic Test for the Serodiagnosis of Abdominal Cystic Echinococcosis in the Peruvian Highlands

We evaluated the performance of a commercial rapid diagnostic test (RDT) in a field setting for the diagnosis of abdominal cystic echinococcosis (CE) using sera collected during an ultrasound population screening in a highly endemic region of the Peruvian Andes. Abdominal CE was investigated by ultrasonography. Sera collected from individuals with abdominal CE (cases) and age- and gender-matched volunteers with no abdominal CE (controls) were tested independently in two laboratories (Peru and Italy) using the VIRapid® HYDATIDOSIS RDT and RIDASCREEN® Echinococcus IgG enzyme-linked immunosorbent assay. Performance indexes of single and serially combined tests were calculated and applied to hypothetical screening and clinical scenarios. Test concordance was also evaluated. Prevalence of abdominal CE was 6.00% (33 of 546) by ultrasound. Serum was obtained from 33 cases and 81 controls. The VIRapid test showed similar sensitivity (76% versus 74%) and lower specificity (79% versus 96%) than results obtained in a hospital setting. RDTs showed better performance when excluding subjects reporting surgery for CE and if weak bands were considered negative. Concordance between tests was moderate to very good. In hypothetical screening scenarios, ultrasound alone or confirmed by RDTs provided more reliable prevalence figures than serology alone, which overestimated it by 5 to 20 times. In a simulation of case diagnosis with pre-test probability of CE of 50%, positive and negative post-test probabilities of the VIRapid test were 78% and 22%, respectively. The application of the VIRapid test alone would not be reliable for the assessment of population prevalence of CE, but could help clinical decision making in resource-limited settings.

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Performance Evaluation of Commercial Dengue Diagnostic Tests for Early Detection of Dengue in Clinical Samples

Journal of Tropical Medicine ◽

10.1155/2017/4687182 ◽

2017 ◽

Vol 2017 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Tuan Nur Akmalina Mat Jusoh ◽

Rafidah Hanim Shueb

Keyword(s):

Dengue Virus ◽

Real Time ◽

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Dengue Infection ◽

Clinical Samples ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Serum Samples ◽

Kappa Agreement

The shattering rise in dengue virus infections globally has created a need for an accurate and validated rapid diagnostic test for this virus. Rapid diagnostic test (RDT) and reverse transcription-polymerase chain reaction (RT-PCR) diagnostic detection are useful tools for diagnosis of early dengue infection. We prospectively evaluated the diagnostic performance of nonstructural 1 (NS1) RDT and real-time RT-PCR diagnostic kits in 86 patient serum samples. Thirty-six samples were positive for dengue NS1 antigen while the remaining 50 were negative when tested with enzyme-linked immunosorbent assay (ELISA). Commercially available RDTs for NS1 detection, RTK ProDetect™, and SD Bioline showed high sensitivity of 94% and 89%, respectively, compared with ELISA. GenoAmp® Trioplex Real-Time RT-PCR and RealStar® Dengue RT-PCR tests presented a comparable kappa agreement with 0.722. The result obtained from GenoAmp® Real-Time RT-PCR Dengue test showed that 14 samples harbored dengue virus type 1 (DENV-1), 8 samples harbored DENV-2, 2 samples harbored DENV-3, and 1 sample harbored DENV-4. 1 sample had a double infection with DENV-1 and DENV-2. The NS1 RDTs and real-time RT-PCR tests were found to be a useful diagnostic for early and rapid diagnosis of acute dengue and an excellent surveillance tool in our battle against dengue.

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Field performance of malaria rapid diagnostic test for the detection of Plasmodium falciparum infection in Odisha State, India

The Indian Journal of Medical Research ◽

10.4103/0971-5916.176620 ◽

2015 ◽

Vol 142 (7) ◽

pp. 52 ◽

Cited By ~ 5

Author(s):

K Gunasekaran ◽

SS Sahu ◽

P Jambulingam

Keyword(s):

Plasmodium Falciparum ◽

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Field Performance ◽

Falciparum Infection ◽

Malaria Rapid Diagnostic Test ◽

Plasmodium Falciparum Infection

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Analytical Evaluation of Dried Blood Spot and Rapid Diagnostic Test as a New Strategy for Serological Community Screening for Chronic Chagas Disease

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.736630 ◽

2021 ◽

Vol 11 ◽

Author(s):

Aroa Silgado ◽

Lídia Gual-Gonzalez ◽

Adrián Sánchez-Montalvá ◽

Inés Oliveira-Souto ◽

Lidia Goterris ◽

...

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Chagas Disease ◽

Latin American ◽

Whole Blood ◽

Enzyme Linked Immunosorbent Assay ◽

Lower Sensitivity ◽

Blood Samples ◽

Screening Programs ◽

Chronic Chagas Disease

BackgroundChagas disease is a public health problem not only in Latin America, but also in other regions, including Spain, due to migration movements. Conventional serological diagnosis requires an invasive sample (plasma or serum) and a well-equipped laboratory. To circumvent those limitations, blood samples dried on filter paper (DBS) or Rapid Diagnostic Test (RDT) could be a practical alternative to reference protocol for serological screening in epidemiological studies. We evaluated the usefulness of dried blood sampling and a rapid diagnostic test (Trypanosoma Detect™) for the detection of antibodies against T. cruzi for their use in community-based screening.Methodology/Principal FindingsA total of 162 stored paired whole-blood and serum samples from Latin American migrants and 25 negative-control blood samples were included. Diagnosis of chronic Chagas disease was performed in serum according to WHO algorithms. Blood samples were retrospectively collected as dried spots and then analyzed using two different serological techniques, enzyme-linked immunosorbent assay (ELISA) and electrochemiluminescence immunoassay (E-CLIA). Whole-blood samples were also used to evaluate a rapid diagnostic test based on immunochromatography. A better correlation with conventional serum was observed in dried blood elutes using E-CLIA than ELISA (97% vs. 77% sensitivity, respectively). Both assays reported 100% specificity. The median cut-off index values of E-CLIA for dried blood were significantly lower than those for serum (138.1 vs. 243.3, P<0.05). The Trypanosoma Detect™ test presented a sensitivity and specificity of 89.6% and 100%, respectively.ConclusionsThe detection of antibodies against T. cruzi in dried blood samples shows a higher sensitivity when using E-CLIA compared with ELISA. Trypanosoma Detect™ is easier to use but has a lower sensitivity. Hence, we propose a sequential strategy based on performing the rapid test first, and a negative result will be confirmed by DBS-ECLIA for use in community Chagas disease screening programs.

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Large-scale evaluation of a rapid diagnostic test for human cystic echinococcosis

Diagnostic Microbiology and Infectious Disease ◽

10.1016/j.diagmicrobio.2017.06.002 ◽

2017 ◽

Vol 89 (1) ◽

pp. 20-25 ◽

Cited By ~ 6

Author(s):

Alice Baraquin ◽

Houria Zait ◽

Florence-Elisabeth Grenouillet ◽

Elise Moreau ◽

Boussad Hamrioui ◽

...

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Cystic Echinococcosis ◽

Large Scale ◽

Scale Evaluation ◽

Human Cystic Echinococcosis

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Imported Malaria confirmed by immuno-assay

QJM ◽

10.1093/qjmed/hcaa060.003 ◽

2020 ◽

Vol 113 (Supplement_1) ◽

Author(s):

S S Abdelgawad ◽

E Y Abusarea ◽

R M Shaapan ◽

M A Ghieth

Keyword(s):

Diagnostic Test ◽

Rapid Diagnostic Test ◽

Parasitic Infection ◽

Blood Film ◽

Antigen Detection ◽

Imported Malaria ◽

Confirmatory Test ◽

Endemic Region ◽

Malaria Antigen ◽

Kappa Agreement

Abstract Background Malaria is the most clinically critical parasitic infection worldwide with undesirable morbidity and mortality. Aim of the Study This study detected the efficacy of rapid diagnostic test for detection of imported malaria among patients with history of fever and/or had travelled to malaria endemic region. Subjects and Methods Blood samples were collected through a year from 732 patients attending three medical laboratories at El Wasta city, Beni-Suef, Egypt. Malaria was tested using thin and thick Geimsa stained blood film and rapid diagnostic test (RDTs) for immunological detection of malaria antigen. Results Microscopy reveled malaria in 4 samples (0.5%) distributed as follow, P. vivax, P. falciparum, mixed P. falciparum and P. vivax infection (0.5%, 0.25%, 0.25%, respectively). Antigen detection was positive in 7 cases (0.9%) with maximum sensitivity, satisfied specificity (100%, 98.5%, respectively) and substantial Kappa agreement (0.677). All positive samples for malaria by microscopy were confirmed by malaria antigen detection. All positive samples by microscopy and/or immune-assay were traveled to Sudan (71.4%) or Yemen (28.6%). Conclusion Sudan is considered a major focus for imported malaria in Egypt, much restriction rules are needed for travellers and immigrants. Antigen detection using RDTs is a satisfied confirmatory test for suspected cases with fever history.

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